Function pluginDynamicComp

pkg/cmd/load_plugins.go:335–404

pluginDynamicComp call the plugin.complete script of the plugin (if available) to obtain the dynamic completion choices. It must pass all the flags and sub-commands specified in the command-line to the plugin.complete executable (except helm's global flags)

(plug plugin.Plugin, cmd *cobra.Command, args []string, toComplete string)

// to obtain the dynamic completion choices.  It must pass all the flags and sub-commands
// specified in the command-line to the plugin.complete executable (except helm's global flags)
func pluginDynamicComp(plug plugin.Plugin, cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {

	subprocessPlug, ok := plug.(*plugin.SubprocessPluginRuntime)
	if !ok {
		// Completion only supported for subprocess plugins (TODO: fix this)
		cobra.CompDebugln(fmt.Sprintf("Unsupported plugin runtime: %q", plug.Metadata().Runtime), settings.Debug)
		return nil, cobra.ShellCompDirectiveDefault
	}

	var ignoreFlags bool
	if cliConfig, ok := subprocessPlug.Metadata().Config.(*schema.ConfigCLIV1); ok {
		ignoreFlags = cliConfig.IgnoreFlags
	}

	u, err := processParent(cmd, args)
	if err != nil {
		return nil, cobra.ShellCompDirectiveError
	}

	// We will call the dynamic completion script of the plugin
	main := strings.Join([]string{plug.Dir(), pluginDynamicCompletionExecutable}, string(filepath.Separator))

	// We must include all sub-commands passed on the command-line.
	// To do that, we pass-in the entire CommandPath, except the first two elements
	// which are 'helm' and 'pluginName'.
	argv := strings.Split(cmd.CommandPath(), " ")[2:]
	if !ignoreFlags {
		argv = append(argv, u...)
		argv = append(argv, toComplete)
	}

	cobra.CompDebugln(fmt.Sprintf("calling %s with args %v", main, argv), settings.Debug)
	buf := new(bytes.Buffer)

	// Prepare environment
	env := os.Environ()
	for k, v := range settings.EnvVars() {
		env = append(env, fmt.Sprintf("%s=%s", k, v))
	}

	// For subprocess runtime, use InvokeWithEnv for dynamic completion
	if err := subprocessPlug.InvokeWithEnv(main, argv, env, nil, buf, buf); err != nil {
		// The dynamic completion file is optional for a plugin, so this error is ok.
		cobra.CompDebugln(fmt.Sprintf("Unable to call %s: %v", main, err.Error()), settings.Debug)
		return nil, cobra.ShellCompDirectiveDefault
	}

	var completions []string
	for comp := range strings.SplitSeq(buf.String(), "\n") {
		// Remove any empty lines
		if len(comp) > 0 {
			completions = append(completions, comp)
		}
	}

	// Check if the last line of output is of the form :<integer>, which
	// indicates the BashCompletionDirective.
	directive := cobra.ShellCompDirectiveDefault